WO 98/00730 discloses a system for avoiding collisions when reversing. Objects located behind the vehicle are detected by means of an ultrasonic sensor or microwave sensor and the distance of the objects from the vehicle is determined. The distance is indicated acoustically and displayed in text form to the driver of the vehicle. If the distance becomes less than a predefined threshold value, a braking actuator is automatically activated in order to bring the vehicle to a stop in good time before a collision. In addition, a braking effect can be brought about by means of the engine. This system is used exclusively for avoiding collisions, that is to say it intervenes just before a collision with an object. Reversing per se is performed by the driver of the vehicle alone.